class_docstr: Parent class for LLMFnOutputs.
  
  This class exists mainly to avoid a circular dependency between LLMFnOutputs
  and LLMFnOutputsSink. Most users should use LLMFnOutputs directly instead.
code: def __getitem__(self, x: int) -> LLMFnOutputEntry:
      ...
  
imports: from __future__ import annotations
  import abc
  import dataclasses
  from typing import overload, Any, Callable, Iterable, Iterator, Mapping, Sequence
  from google.generativeai.notebook.lib import llmfn_output_row
  from google.generativeai.notebook.lib import model
  import pandas
label_desc: Use image node_id 4 for calling the LLMFnOutputsBase obj's underlying member method code with example usage: obj.__getitem__(x) without return types